REAL-TIME

A build · Multiplayer game

I Call On.

A fast-paced party game that tests how quickly you can think under pressure — built around real-time synchronisation, fairness, and repeat play.

Overview

A simple concept with a hard system underneath.

I Call On is a real-time multiplayer naming game for friends and families. The caller picks a letter; everyone else races to name an animal, a place, or a person starting with that letter — before the caller stops the round. Score points for valid answers, move through the categories, and see who pulls ahead.

What makes the game work isn't the concept — it's the execution. The experience depends entirely on speed, synchronisation, and fairness across every player in real time. When the round ends, it has to end for everyone, instantly. A half-second delay breaks the whole thing.

TypeA GrayTop build

FocusGame design · UX · Frontend · Real-time logic

Stack

React Native Custom game logic Real-time sync

SYNCHRONISE

The challenge

Making real-time gameplay feel fair and instant

"Even small delays break the experience."

The core challenge wasn't the game idea — it was the system behaviour. When the caller ends a round, all players must stop instantly. Inputs from multiple users have to be captured and scored fairly. Network delays can create inconsistencies between players — one phone still accepting answers while another has already locked.

Without tight synchronisation, the game quickly feels unreliable — and a party game that feels unreliable doesn't get played twice. The architecture had to deliver near-instant state updates across every connected device, regardless of network conditions.

What I built

The system behind the game.

sync_alt

Synchronised round control

The caller controls the round lifecycle, and every player device stays in sync when rounds start and stop. When the caller presses stop, every phone stops — simultaneously, across variable mobile connections.

keyboard

Real-time input handling

Players submit answers at the same time, with logic to capture, validate, and score responses inside the time window — keeping it fair regardless of who answers first or how fast their connection is.

groups

Caller / player role system

Distinct flows for the caller, who controls round pacing, and players, who compete to answer. Each role gets a different interface — keeping the dynamic clear without needing a tutorial.

emoji_events

Lightweight scoring engine

Points awarded on valid entries across categories, with a game loop kept intentionally lean: fast rounds, minimal friction, high replayability. Easy to start, difficult to put down.

System insight

I Call On is a timing-sensitive system.

Simple concept + complex synchronisation requirement

Variable network conditions → consistent, fair experience for all players

Caller stops the round → everyone stops, simultaneously

Even with a simple concept, the complexity lives in making the experience feel instant and fair for everyone in the room. That's the part worth building well — and the part off-the-shelf tooling never quite gets right.

More work

Internal tool · AI system

Content OS

An autonomous content engine that audits posting history, finds the gaps, writes five complete scripts, and delivers them every Monday.

View case study →

Got a
build in
mind?

Whether it's a product to ship or a workflow to automate, take the 2-minute diagnostic. It tells you the honest move — and sometimes the answer is "not yet."

Start the diagnostic → Just email me